does anyone have a schematic for this console.
2nd question does anybody have an idea why the direct outs which are posteq/prefader are that low( i mean really low) levelwise?
any help would be nice.
Regards
Oliver

I think your problem is most other people's desire... ( I mean the schematic searching. As far as the level output, it could be that it's setup for -10dBu, or possibly even lower. I imagine these do not have XLR balanced outputs right?)

If I'd have this and couldn't find the schematics I'd draw it myself. Even if it takes hours and hours and hours....

Does it have op amps? Looks 1973-1978-ish to me. I am almost certain these would use transistors and inductor based EQ circuits.

regards

2N1305

Last edited by 2N1305; 9th May 2010 at 10:34 PM..
Reason: forgot information and clarification

thanks so far for your help.
it does have xlr ins and outs and siemens type direct outs, but those are unbalanced, but i wanna make it transformer balnaced.
indeed it sounds really beautiful.
i can post more pictures next days also from the innerside of it.
maybe anybody of you could help again.
thanks.

it wasn't until today when I reread your question did I realize exactly what you said. You had said "..why the outputs (which are posteq/prefader) are that low..."
Well the answer might well be because it is posteq. I don't know what to expect, but what signal were you putting in? Also, how do you determine that the signal coming out is really low?

it wasn't until today when I reread your question did I realize exactly what you said. You had said "..why the outputs (which are posteq/prefader) are that low..."
Well the answer might well be because it is posteq. I don't know what to expect, but what signal were you putting in? Also, how do you determine that the signal coming out is really low?

Inside Pictures! yes! heh

2N

well, i put in a mic put a cable from the direct outs to converter input and the level is really low.
what does it have to do with the eq?
even if i null the eq it doesn't change a thing.

OK, when you say converter you mean the A/D converter in your computer?

It might be the input level of your converter that is too low...

Can you see anything on the VU meters? (of the Chilton)

the converter is a ssl alphalink converter.
but i had it at my maintenance engineer today.
he also said, could be -10, because the bbc used to work with the direct outs a lot with"hifi" equipment(tape machines)
But he gave a really nice 8 channel transformer rack .
an active one where you can also boost levels and calibrate levels.
Im waiting for the cables, and gonna test with that unit.
could work.

Hi, I'm upgrading my M10 this week! Mine is mic pre-amp module to line in connector(pre amp module bypassed once connected) to mid eq module(1.5k or 3k additive only) to low + hi eq modules to aux 1 and 2 to fader to mix(summing) module to master fader to line amp module to compressor to Xformer to output conector. On mine the eq is not set up the same and I don't have direct outs, but I can check on another beat up console I have. I believe they are post eq. I have done some direct outs post eq on mine and they were are pretty low (around -10 would be a good guess) as is but I've added a line amp module(+10 db according to the QM3 schematics) and they are quite OK level wise. So you should be OK with that active line booster you've got. I traced out some schematics but haven't double checked them yet. It doesn't seem to share much with the QM3 exept maybe the line amps. Mine was huge mess, picking up radio, hum,... I recapped the whole thing, repaired faulty wiring, added phase, mute and pads, added routing switches, added mid eq modules... but it was worth it. A little "dark" and "slow", but lots of "character". On mine each modules (pre amp, mix, line amp, eq) serves 2 channels, but there are different versions.... they are printed on the PCB ex. line amp = LA2. Take pictures!

Hi, I'm upgrading my M10 this week! Mine is mic pre-amp module to line in connector(pre amp module bypassed once connected) to mid eq module(1.5k or 3k additive only) to low + hi eq modules to aux 1 and 2 to fader to mix(summing) module to master fader to line amp module to compressor to Xformer to output conector. On mine the eq is not set up the same and I don't have direct outs, but I can check on another beat up console I have. I believe they are post eq. I have done some direct outs post eq on mine and they were are pretty low (around -10 would be a good guess) as is but I've added a line amp module(+10 db according to the QM3 schematics) and they are quite OK level wise. So you should be OK with that active line booster you've got. I traced out some schematics but haven't double checked them yet. It doesn't seem to share much with the QM3 exept maybe the line amps. Mine was huge mess, picking up radio, hum,... I recapped the whole thing, repaired faulty wiring, added phase, mute and pads, added routing switches, added mid eq modules... but it was worth it. A little "dark" and "slow", but lots of "character". On mine each modules (pre amp, mix, line amp, eq) serves 2 channels, but there are different versions.... they are printed on the PCB ex. line amp = LA2. Take pictures!

nic

hi,

i think mine are the same amps.
by the end of the week i got all cales together, so i can check the transformer upgrade.
i'll let you know.
post some pics!!!
o

I have a QM3 here. I even met the man who made these, Tom Repps.
The desk is discrete as far as the fader, and the busses. After that it uses opamps. 5534's generally. The PSU is +24V. The outputs clip around +20dB
Very low by todays standards, and won't drive modern converters fully.
The insert and I guess 'direct' outs are around -10dB. That's the way it is.
That series Quiet Mixer, is extremely quite. Great for ribbon mics. Beat many preamps in tests here, including a Neve 9098.
Note the pad is after the first pre stage. If your gain pot is around 9-10 O Clock there is great danger of input overload.
A gem.
DD

Hi
-10dBu is quite likely as it would be an attempt to have anything like decent headroom as observed you can only get about +19dBu from a 24 Volt supply rail unbalanced.
If your convertors have a minus 10 setting, use it otherwise you could investigate a 'line amp' modification using either Chilton or other amplifier cards.
The usual BBC requirement was for 36dB headroom above line up (0dBu) PREFADE (for mic inputs) so that artistes yelling could be tamed without having to use a coarse gain control. In view of this original compromise it would likely have been fed into external line amplifiers.
Other 24 Volt desks such as the Audixes of that time used a transformer drive stage with a 1:2 step up transformer to give at least 24dBu.
Matt S

Check that those Direct Outs are not Post Fader or Post Eq and Fader. I have seen that. Easily modified to Pre. Incidentally the Insert is probably immediately after the Preamp, you could take your signal there, using a bridged stereo jack. i.e. Short tip to ring and take the signal from there.
DD

This is mine. It is an earlier version. I've added that extra panel on top for the pad, polarity, and low cuts(not there yet). The modules below are line (LA2B), mid EQ (MID AMP c), and mic pre (MT Mic). It is also possible to bypass the eq on the mid amp eq and just use it as an amp for extra gain (and extra noise...) but I haven't found a need for that yet. I have set up my sound card for -10db (on master and AUX out) and my modified direct out are at +4. The headroom is a little low on mine too....

Thanks for all your infos.
Today i got it all working and sounding fine.
I used an external active Transformer box with haufe transformers.
Level could be boosted 20 and 10 db with fine trim.
Very nice,
sounds excellent.
Some pictures of the console here.

I have a QM3 here. I even met the man who made these, Tom Repps.
The desk is discrete as far as the fader, and the busses. After that it uses opamps. 5534's generally. The PSU is +24V. The outputs clip around +20dB
Very low by todays standards, and won't drive modern converters fully.
The insert and I guess 'direct' outs are around -10dB. That's the way it is.
That series Quiet Mixer, is extremely quite. Great for ribbon mics. Beat many preamps in tests here, including a Neve 9098.
Note the pad is after the first pre stage. If your gain pot is around 9-10 O Clock there is great danger of input overload.
A gem.
DD

Hi
-10dBu is quite likely as it would be an attempt to have anything like decent headroom as observed you can only get about +19dBu from a 24 Volt supply rail unbalanced.
If your convertors have a minus 10 setting, use it otherwise you could investigate a 'line amp' modification using either Chilton or other amplifier cards.
The usual BBC requirement was for 36dB headroom above line up (0dBu) PREFADE (for mic inputs) so that artistes yelling could be tamed without having to use a coarse gain control. In view of this original compromise it would likely have been fed into external line amplifiers.
Other 24 Volt desks such as the Audixes of that time used a transformer drive stage with a 1:2 step up transformer to give at least 24dBu.
Matt S

i boosted the all direct outs about 20 db with the external haufe transformer box.
good working level for me now.

Check that those Direct Outs are not Post Fader or Post Eq and Fader. I have seen that. Easily modified to Pre. Incidentally the Insert is probably immediately after the Preamp, you could take your signal there, using a bridged stereo jack. i.e. Short tip to ring and take the signal from there.
DD

This is mine. It is an earlier version. I've added that extra panel on top for the pad, polarity, and low cuts(not there yet). The modules below are line (LA2B), mid EQ (MID AMP c), and mic pre (MT Mic). It is also possible to bypass the eq on the mid amp eq and just use it as an amp for extra gain (and extra noise...) but I haven't found a need for that yet. I have set up my sound card for -10db (on master and AUX out) and my modified direct out are at +4. The headroom is a little low on mine too....

Might be more like 10:30 heh
In any case be aware that the first stage is before that gain pot. It can be overloaded. I also seem to remember I didn't like the pad.
Good luck with the old girl. They called these the poor man's Neve.
DD

hi guys, just looking at this thread. is anybody interested in buying a m10-2 mk5 mixer. I have one, the power supply went bang BIG TIME and is now 'dustbinized'. The actual desk is in working order although a couple of the knobs went south a while back.

Ive picked up a nice looking Chilton M10/2 , seems to be in great condition. I havent powered it up as I dont have the psu so that is my first job, shouldnt be too hard I guess . On first inspection I thought it was only line ins but I was happily suprised to find 3 modules of two mic amps inside. It does confuse me that there is no mic line switching and no labelling . I dont see any mic powering options so p48 is another issue . It does look like a nice vintage piece just hope it can be tuned up as I was looking for a mixer with character . I know schematics have been asked and searched for, I'm presuming to no avail ?.... So if anyone has a power supply that can point me at some wiring and a rough circuit I would be grateful . I will inspect further.

Hi
An alternative would be to buy a 'Power One' 24 Volt DC module and a 48 Volt module and mount them in a box. This at least takes much of the effort out of getting a supply together.
The Chilton supply is pretty simple anyway, a LM338 for the 24 Volt rail.
Just depends how much effort you want to put into it.
Matt S